Minimum CYA to slam?

tdp

LifeTime Supporter
Sep 16, 2015
57
Suburban Philadelphia
#1
Pool just opened today; readings are

(Water mostly clear, not green, but a lot of dirt/debris with what looks like a small amount of algae on one seat. Pool was closed in Oct.)
water temp 56F
FC 1.5
CC 5.5
TA 70
Ca++ 150
CYA 0 (I let water sample for CYA test warm up on top of a running clothes dryer so it was warmer)
Salt 2400
pH ~7.3-ish

Questions:
1) I clearly need to slam; what is the minimum CYA for a slam?
(I will need to get the CYA up to ~70 eventually for SWG, but assume I can get by with much less while slamming, then raise CYA after, since higher CYA=more chlorine for slam?)
2) in what order should I slam and adjust the other chemistries?

Thanks!
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,285
NW Ohio
#2
Your CC level tells me there is a problem that needs to be corrected before you add CYA. Follow these steps before adding CYA to your pool:

Dose chlorine up to 10 ppm FC.
Retest FC and CC after 10 minutes.
If FC is less than 5 upon retest repeat above
Once you get an FC reading above 5 (could be right away, could take a few rounds) then you can add 30 ppm CYA and begin your SLAM. Once you complete your SLAM you can increase your CYA to the correct level for SWG use and settle in to your normal routine.
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,285
NW Ohio
#4
Glad to hear. I would bump it back up to 10 for the overnight, since your pH is already fine there's no reason not to keep the FC level up and get a jump on the SLAM.